<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <style>
        canvas {
            border: 1px solid red;
        }
    </style>
    <script type="text/javascript" src="js/clock.js"></script>
</head>
<body>
    <canvas width="800" height="600"></canvas>
</body>
</html>
<script>
    var canvas = document.querySelector("canvas");
    var ctx = canvas.getContext("2d");

    var clock = new Clock({
        ctx: ctx,
        bigX: canvas.width / 2,
        bigY: canvas.height / 2,
        bigRadius: 200
    })
</script>